Technical Field
Embodiments of the subject matter disclosed herein relate to a fuel system for an engine.
Discussion of Art
The regulation of fuel pressure in a fuel rail may be provided by one or more inlet metering valves, which throttle the flow of fuel into the inlet of the high-pressure fuel pump upstream of the fuel rail. In this manner, fuel may be supplied to the fuel rail at a rate matched to the flow rate out of the rail due to fuel injection. Over time, the inlet metering valve may become degraded due to bearing degradation, for example, leading to a slower response to commanded valve position changes. Such valve degradation may result in fuel rail under- or over-pressure events, causing fuel injection errors and/or fuel rail or fuel injection degradation.